Tag Archives: TTL

Post navigation

Say that you are ready to take a TTL flash shot. Once you have set your camera to a certain ISO and aperture and flash exposure compensation, and you have decided how to point the flash, you can do your test shot.

Say it is too dark. Why? Is it “incorrect metering, subject too light, etc”, or is it just “not enough power at this ISO/Aperture” (the shutter makes no difference)?

To ascertain that, and to see how much reserve you have, set your flash to manual, full (1/1) power:

The example shows half power (1/2); you should select full power (1/1, or 100%).

If you now have an overexposed picture, you know you can do the shot. Go back to TTL (press “mode” until “M” changes to “TTL”) and try again, changing flash compensation until your picture is good.

But if instead, your picture is too dark still, then there is simply insufficient power available. So no amount of flash compensation or metering changes will help. Instead, you have to lower the F-number or increase the ISO until that is no longer the case. (Or you could move to a room with a lower ceiling, if you are bouncing the flash).

I.e. if I were to sum this up, I would say:

Never go to TTL unless in full power manual, your picture is overexposed.

Simple, no? But you would be surprised how many photographers struggle with this simple check.

My face is underexposed totally compared to the rest of the shoot, which was like this:

So there the sides of my face are well exposed. But then the photographer zoomed out, and we got the shot at the top. What gives?

If you do not know, let me give you a hint: we were using TTL.

If you still do not know, allow me to explain:

TTL is like “auto for flash”.

Auto flash exposure normally uses evaluative (“Matrix”) metering.

I.e. the screen is divided into little squares, dozens or hundreds of them, and each one is metered individually.

As soon as any of these little squares are overexposed, even one of them, the camera tries to fix that.

It does that by lowering the exposure. But you obviously cannot change just one part of the photo, so the entire exposure is lowered.

That’s the reason the picture at the top is underexposed: the flashes are visible, meaning a hot spot or two, and the camera “fixes” that by lowering the entire exposure (by using a lower flash power setting).

The fix: You can go to average metering. Or you can avoid hotspots like reflections or flashes.

That’s one of the little facts you learn if you take my flash course.

Are you aware that virtually all my courses are offered online as well? Live, one-on-one courses, like the one I just did today with a long-time reader from Melbourne, Australia:

If you go to this page and check the pull-down menu, you will see that you can even save money by doing it online. So wherever you are in the world, I would be delighted to do a one-on-one with you.

Often, my posts point out common myths and misconceptions. Of which there are many… many. On the Internet, no-one knows that you’re a dog, and no-one knows that you are wrong.

So, two oft-heard “truths”:

You cannot shoot with TTL if you are a pro.

You cannot use just one light for a serious portrait.

So. TTL was used in this portrait of students and friend Diana; remote TTL in fact (light flashes from on camera flash drives off camera flash); and the light was one flash through an umbrella. The on camera flash was disabled, except for those light flashes.

1/125 sec, f/8, ISO100.

The curtain was chosen as a classy background, but the umbrella was close to the subject so the curtain would get little light. TTL handles this fine; if the subject had been too light or too dark, a touch of flash compensation would have sorted that out.

The one light-with-umbrella gives us enough light for a portrait with Rembrandt lighting. Fairly dramatic chiaroscuro-type lighting, but not so dramatic that it becomes unflattering. On the contrary, this is nice light.

The blonde hair stands out nicely against the dark background; dark hair would have needed more light.

So there, a real portrait with “studio settings”, i.e. just one light, and using TTL. I could do that all night.

Today, another example of the “Amateur Aesthetic” or “Snapshot Aesthetic”made popular by such contemporary photographers as Terry Richardson, after Diane Arbus and Nan Goldin, two of my favourites.

Here’s mine, a high-key model shot:

We call it amateur, or snapshot, because you use a flash straight on, and aim at the subject, and have the subject stand in front of a white backdrop, camera aware. Like Uncle Fred does. This gives you the drop shadow. It also, however, gives you very flattening light, and models like this: it hides any facial features. Overexposing a little, or rather, exposing brightly, makes it even better in that regard.

Unlike your Uncle Fred, my models and I think carefully about composition, light, and expression and pose. The direct flash means you need to aim the subject’s face down a little, else light comes “from below”, which is never flattering.

So nothing is left to accident, in spite of the amateur look.

For this shot, I used 1/160th sec, 400 ISO, f/5.6 and an on-camera 600EX flash. The flash compensation, like in the examples of a few days ago, was set to +2 stops, and I used TTL flash metering for flexibility.

Your assignment for today: shoot a portrait like this. I am about to teach a TTL flash course, and my student will do this as well. In addition to “proper” flash, you need to know techniques like this as just another tool in your toolbox.